Assistant Chief Vern Malloch said two men have died since the beginning of December from what is believed to be heroin overdoses.

Another eleven people have been treated for overdoses requiring life-saving treatment, and Malloch said Friday that four of the overdoses have occured in just the last four days.

"If you suspect a friend or loved one has overdosed on heroin, you need to call 911 immediately, because minutes will save their life," Malloch said. "Don't wait and hope they are going to come out of it. If they are unconscious, and there's any kind of respiratory distress, call 911 immediately."

Police say they aren't sure where the strain is coming from at this point.

Anyone with information is asked to contact the Portland Police Department at 207-874-8533.

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